Topic: Oil for SOHC4 bikes (CB650Z)

[Hush]

OK done to death probably but I usually only read those subjects pertinent to my specific problem at the time and I have negligently let the past discussions slip past me.
I checked out the FAQs on engine oil for these old bikes and the reccomendation was 10w/40, I'm presently running 15/50 which is about all you can get specifically for bikes over here.
After losing a flat-out drag race to my partner yesterday I definately feel the clutch is slipping on heavy acceleration (no seriously it's not just cos she's a girl and her bike is 250cc less than mine) and I see mentioned in the FAQs that this can be a side effect of running too thin oil in the sump.
I'm just not sure why oil companies reccommend the 15/50 for all bikes?
If I put car oil in (10w-40) there should be no detriment to my bike right?
Oil is oil is oil right, OK let the flaming begin, just add some constructive stuff too so I'll feel better.

[bucky katt]

i'll bring the beer if someone else brings popcorn and chairs 

[Gordon]

Holy crap, Hush!  You know better than this!

Don't blame the oil.  Either she rides more balls out than you do, or you need new clutch plates. 

[BobbyR]

How much does she and the bike weigh. Power to weight may be your problem not the O word. 

[bender01]

I had some slippage last week. Adjusted the cable and problem solved. Rattle went away too. Maybe thats all you need.

[manjisann]

Oy Hush, maybe Jaffa fiddled with your carbs again 

From what I understand if you use the wrong automotive oil in your sump it'll cause definate slippage. The thing you want to avoid is any of the oil with the slippery additives (sorry, technical term is eluding me at the moment  ) as this will cause the needed friction in the clutch plates to be nonexistant. Just a thought, dunno if that is your issue or not.

Could it just be that she's a better rider than you??? I mean, don't blame the machine, it's only as good as the human piloting it 

Brandon

[MCRider]

i'll bring the beer if someone else brings popcorn and chairs 

All right another OIL THREAD!  Let's ROLL!

Oh you said constructive...

Change the oil to ...ANYThING... put the same oil in her bike... and practice your technique.  

[Hush]

I've done 800 miles since putting the bike back together so probably due for a change just to check for particles.
The proper motorbike stuff (15/50) is quite expensive anyway so something that aids friction in clutch will definitely be cheaper.
Quite annoyed as only 3 weeks ago I slackened all the clutch adjustments right off then started from scratch again and the clutch was really good, for it to slip out of adjustment so quick is crazy.
But it is definitely slipping on acceleration, no old 400 Suzuki is gonna get away with that!

[bucky katt]

my 750 did that until i adjusted it properly at the clutch cover. works a treat now

[mcpuffett]

Hi Hush 10w40 mineral oil for cars from Halfords here in the uk is what i use  , no issues , if you go for a oil that is labelled for bikes it usually costs you more anyway thats what i've found, , cheers Mick.

[scunny]

say it isn't so Hush.

[KeithB]

OK ...I'll bite...
It's not so much the rating of the oil as it is the additives.
For bikes, it's better to use oil that is not listed as "energy conserving" There is a round label on the container and it should have something written in the bottom area.
If it says "energy conserving" , don't use it.
If there is nothing written there it's OK to use.
Diesel engine oils are usually not listed as 'energy conserving" and are better formulated to prevent clutch slippage.

[wrenchmuch]

Forget the oil . I recommed a bigger bore and head work . And just to be safe mess withher carb adjustments when she's not looking .

[rm56]

I run Valvoline 10-40 in mine, I did hear my clutch slip once but not since. I don't ride my 74 hard, no wheelie's, crazy crap like that. You said she was on a 500? Which one? I recognised the avatar from the triple board. Now for the sake of argument, if she is lighter than you, on a Kawasaki 500 triple, and a decent rider, she will beat you from a standing start drag. You will eventually pass her with more top end speed but the stock Honda 750 will not pull a stock triple off the line. 1969-1978 SOHC Honda CB 750s were not designed to use synthetic oil. Some argue they can go further between changes but the costs don't make sense. I'm just not sold on synthetics. I did'nt like Disco either. I always laugh when I read ads for cars and bikes and they say how "It just had all the fluids changed and I only use synthetics". If its not broken, don't fix it!

[jeepster]

Extra virgin olive oil has the most flavor, but also the lowest smoking point. So for frying I like peanut or a good canola oil, for salads and bread trevi umbria extra virgin from fairway is a sure bet. Only $12 too!

[Laminar]

I run Valvoline 10-40 in mine, I did hear my clutch slip once but not since. I don't ride my 74 hard, no wheelie's, crazy crap like that. You said she was on a 500? Which one? I recognised the avatar from the triple board. Now for the sake of argument, if she is lighter than you, on a Kawasaki 500 triple, and a decent rider, she will beat you from a standing start drag. You will eventually pass her with more top end speed but the stock Honda 750 will not pull a stock triple off the line. 1969-1978 SOHC Honda CB 750s were not designed to use synthetic oil. Some argue they can go further between changes but the costs don't make sense. I'm just not sold on synthetics. I did'nt like Disco either. I always laugh when I read ads for cars and bikes and they say how "It just had all the fluids changed and I only use synthetics". If its not broken, don't fix it!

650cc - 250cc = 400cc

Avoid the leftmost two:

[Deltarider]

Btw, why is it the Owners Manual advises a 6000 km interval for an oilchange for the CB650, whereas Honda advises a 3000 km interval for the other Fours?
Since this was shown to me, I maintain a 6000 km interval for my CB500. Engines are similar, aren't they and the 650 even runs a bit hotter.

[BobbyR]

[bucky katt]

Extra virgin olive oil has the most flavor, but also the lowest smoking point. So for frying I like peanut or a good canola oil, for salads and bread trevi umbria extra virgin from fairway is a sure bet. Only $12 too!

i always thought canola smoked before oilve 

[jeepster]

Extra virgin olive oil has the most flavor, but also the lowest smoking point. So for frying I like peanut or a good canola oil, for salads and bread trevi umbria extra virgin from fairway is a sure bet. Only $12 too!

i always thought canola smoked before oilve 

A common newbie mistake. A good, i.e. refined canola oil doesn't smoke till 400 degrees or so:

http://www.goodeatsfanpage.com/CollectedInfo/OilSmokePoints.htm

Peanut oil is ideal, but hella expensive. Highest temp on the chart is avocado oil... which sounds like it would make some wicked tasting french fries.  Any avacado oil users out there care to back this up? Better tasting fries?

[Hush]

I think I'll just squeeze her GSX400 until I get some Suzuki oil out of her bike!
Geez did someone suggest I was trying to drag a Mach1? Even worse that I'd put my Jaffa on one of those rocket rails...heck no!
I was raised on Kwaka 500 triples, seats like a board, faster than any four stroke and a power band that will (and has) dislodge you from the seat.
Nah I needed something way more pedestrian for her, I just didn't realise how quick those old Suzuki four stroke twins were.
Luckily she's not throttle happy and is still green as when riding until she gets her confidence back, then I'd say all bets are off.
I see an oil change in my bike's future after reading some of the replies, thanks guys.

[george]

What about using 15-50 and adding pods without re-jetting ?
I got outran by a girl on a Ninja 250 but I caught her after my bike started !
evoo vs. canola : canola